Semiconductor device having lead terminals bent in J-shape

A method of manufacturing a semiconductor device, comprising the steps of:

• forming a single lead frame wherein a single radiating plate having at least one recess formed on an outer peripheral portion thereof and a plurality of lead terminals are connected integrally to each other by support elements;
• placing a pellet of a semiconductor circuit having a plurality of connection pads provide on a surface thereof onto an upper face of a portion of the lead frame corresponding to the radiating plate;
• connecting the plurality of connection pads of the pellet and the plurality number of lead terminals of the lead frame individually to each other by bonding wires;
• placing the lead frame, on which the pellet and the bonding wires are mounted integrally, into a cavity of at least one pair of mutually removable metal molds such that a lower face of the radiating plate is in direct contact with an inner face of the metal molds and outer portions of the lead terminals are in direct contact with an inner face of the pair of metal molds;
• filling a molten resin into the cavity of the metal molds;
• permitting the filled resin to solidify to form an intermediate product comprising a resin member wherein the pellet, at least a portion of the radiating plate, the bonding wires and inner portions of the lead terminals are encapsulated while the lower face of the radiating plate as well as outer portions of the lead terminals are exposed outside and at least one projection having at least one recess formed on lower faces thereof are formed in the recess of the radiating plate;
• cutting away the support elements of the lead frame of the intermediate product to separate the radiating plate and the plurality of lead terminals individually from one another;
• and
• bending the outer portions of the lead terminals, which extend outwardly from side faces of the resin member, into a J-shape until free ends thereof are positioned within the recess of the radiating plate and also within the recess of the outer peripheral portion of the lower face of the resin member.